Switch to using DI to acquire Node instances. Bump versions to alpha2.

Microsoft.AspNet.NodeServices/HostingModels/HttpNodeInstance.cs

@@ -0,0 +1,50 @@
+using System.Net.Http;
+using System.Text;
+using System.Text.RegularExpressions;
+using System.Threading.Tasks;
+using Newtonsoft.Json;
+using Newtonsoft.Json.Serialization;
+
+namespace Microsoft.AspNet.NodeServices {
+	internal class HttpNodeInstance : OutOfProcessNodeInstance {
+        private readonly static Regex PortMessageRegex = new Regex(@"^\[Microsoft.AspNet.NodeServices.HttpNodeHost:Listening on port (\d+)\]$");
+        
+		private readonly static JsonSerializerSettings jsonSerializerSettings =  new JsonSerializerSettings { 
+            ContractResolver = new CamelCasePropertyNamesContractResolver() 
+        };
+        
+        private int _portNumber;
+		
+		public HttpNodeInstance(int port = 0)
+            : base(EmbeddedResourceReader.Read(typeof(HttpNodeInstance), "/Content/Node/entrypoint-http.js"), port.ToString())
+        {
+		}
+        
+        public override async Task<string> Invoke(NodeInvocationInfo invocationInfo) {
+            await this.EnsureReady();
+            
+            using (var client = new HttpClient()) {
+                // TODO: Use System.Net.Http.Formatting (PostAsJsonAsync etc.)
+                var payloadJson = JsonConvert.SerializeObject(invocationInfo, jsonSerializerSettings);
+                var payload = new StringContent(payloadJson, Encoding.UTF8, "application/json");
+                var response = await client.PostAsync("http://localhost:" + this._portNumber, payload);
+                var responseString = await response.Content.ReadAsStringAsync();
+                return responseString;
+            }
+        }
+        
+        protected override void OnOutputDataReceived(string outputData) {
+            var match = this._portNumber != 0 ? null : PortMessageRegex.Match(outputData);
+            if (match != null && match.Success) {
+                this._portNumber = int.Parse(match.Groups[1].Captures[0].Value);
+            } else {
+                base.OnOutputDataReceived(outputData);
+            }
+        }
+        
+        protected override void OnBeforeLaunchProcess() {
+            // Prepare to receive a new port number
+            this._portNumber = 0;
+        }
+    }
+}